Effect of 1, 25 (OH)2D3 on serum parathyroid hormone levels, bone metabolic markers and muscle strength in the community elderly with low bone mass / 中华老年医学杂志

ABSTRACT

Objective To investigate the intervention effect of 1,25(OH)2D3 on serum level of parathyroid hormone,bone metabolic markers and muscle strength in the community elderly with low bone mass.Methods A total of 132 residents aged 60 years and over from Shanghai communities diagnosed as osteopenia or osteoporosis were enrolled and treated with 0.5 μg/d calcitriol for 3 months.Serum levels of parameters in blood biochemistry and bone metabolic markers were determined by Cobas Diagnosis System of Roche before and after treatment,and the handgrip strength of both left and right hands were measured at the same time.Results The average age of 132 patients was(66.1 ± 6.3) years,4 cases (all female) terminated their medication in advance,and 128 patients completed the treatment for three months.The baseline serum levels of 25 (OH)D and PTH were 19.6 ± 7.9 μg/L and 41.0 μg/L respectively.According to the median value of serum PTH before treatment,patients were divided into the two groups:the high PTH group and the low PTH group.Compared with the low PTH group,the serum levels of 25OHD and serum calcium were decreased in the high PTH group[(17.1 ± 7.0) μg/L vs.(22.1 ± 8.2) μg/L,2.4 mmol/L vs.2.5 mmol/L,P＜0.05].After 3 months of intervention,serum levels of creatinine,urine calcium and left handgrip were significantly elevated[(68.2 ± 13.8) μmol/L vs.(65.2 ± 13.4) μmol/L,(5.9 ± 2.8)mmol/24 h vs.(4.4 ± 2.0) mmol/24 h,23.8 kg vs.21.0 kg,all P ＜0.05],while serum levels of PTH,eGFR,phosphorus were significantly decreased[35.5 ng/L vs.42.0 ng/L,(87.0 ± 17.0) ml/min vs.(93.1±17.9) ml/min,1.2 mmol/L vs.1.3 mmol/L,all P＜0.05).There was a significant negative correlation between serum 25(OH)D and PTH before treatment(r=-0.312,P＜0.05),but the negative correlation between them was no longer significant after 3 months of treatment (r =0.042,P ＞ 0.05).A multivariate logistic regression analysis revealed that the increment of left handgrip strength greater than 25％ (OR =0.138,95％ CI:-0.002-8.383),the increment of serum calcium levels(OR =2.578,95％CI:1.0345-8.693)and age(OR =0.103,95％CI:0.035-0.345) were significantly correlated with the decrement of serum PTH levels greater than 30 ％ after three months of treatment.Conclusions Vitamin D diminution or deficiency is common in the elderly.The shortterm treatment of calcitriol can obviously reduce serum PTH,inhibit bone absorption and increase muscle strength.The effect of calcitriol on serum PTH is closely related to promoting calcium absorption and improving handgrip strength.